rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7661/1:b..l
	(detected by 1, t=10503 jiffies, g=119657, q=6 ncpus=2)
task:udevd           state:R  running task     stack:23040 pid:7661  ppid:3639   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6873
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:696
RIP: 0010:lock_acquire+0x20f/0x490 kernel/locking/lockdep.c:5666
Code: 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 f5 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 66 43 c7 44 3d 09 00 00 43 c6 44 3d 0b
RSP: 0018:ffffc900052878a0 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 93a78ac012e36c00
RDX: 0000000000000000 RSI: ffffffff8a8c1700 RDI: ffffffff8adef760
RBP: ffffc900052879b0 R08: dffffc0000000000 R09: fffffbfff215c449
R10: fffffbfff215c449 R11: 1ffffffff215c448 R12: 0000000000000000
R13: 1ffff92000a50f20 R14: 0000000000000246 R15: dffffc0000000000
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 get_obj_cgroup_from_current+0xec/0x280 mm/memcontrol.c:3019
 memcg_slab_pre_alloc_hook mm/slab.h:485 [inline]
 slab_pre_alloc_hook+0x91/0x310 mm/slab.h:715
 slab_alloc_node mm/slub.c:3279 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x56/0x2f0 mm/slub.c:3383
 vm_area_dup+0x23/0x1a0 kernel/fork.c:467
 __split_vma+0xb9/0x500 mm/mmap.c:2363
 do_mas_align_munmap+0x351/0x1220 mm/mmap.c:2480
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650
 __vm_munmap+0x18d/0x290 mm/mmap.c:2936
 __do_sys_munmap mm/mmap.c:2961 [inline]
 __se_sys_munmap mm/mmap.c:2958 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2958
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd17c91e097
RSP: 002b:00007ffec1670d78 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 00005605b7e46ee0 RCX: 00007fd17c91e097
RDX: 00005605b7e40a48 RSI: 0000000000000200 RDI: 00007fd17c7bc000
RBP: 0000000000000002 R08: 0000000000000030 R09: 00005605b7e59c90
R10: 0000000000000000 R11: 0000000000000246 R12: 00005605b7e470b0
R13: 00007fd17d00239c R14: 0000000000000400 R15: 0000000000000009
 </TASK>
rcu: rcu_preempt kthread starved for 10533 jiffies! g119657 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27296 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
 schedule+0xb9/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x2f2/0x1310 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x95/0x380 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 20939 Comm: syz.3.2938 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:seqcount_lockdep_reader_access+0x3e/0x1c0 include/linux/seqlock.h:97
Code: 00 00 65 48 8b 04 25 28 00 00 00 48 89 44 24 68 48 c7 04 24 b3 8a b5 41 48 c7 44 24 08 8e a6 5c 8c 48 c7 44 24 10 00 46 71 81 <49> 89 e6 49 c1 ee 03 48 b8 f1 f1 f1 f1 00 f2 f2 f2 49 bf 00 00 00
RSP: 0018:ffffc90000007d60 EFLAGS: 00000086
RAX: 88734aabcfa98900 RBX: 0000000000071c58 RCX: ffff8880272e0000
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007e18 R08: dffffc0000000000 R09: fffffbfff1c3ed56
R10: fffffbfff1c3ed56 R11: 1ffffffff1c3ed55 R12: ffff8880b8e2a5d0
R13: dffffc0000000000 R14: ffff8880b8e2a6e8 R15: ffff8880b8e2a6e8
FS:  00007fcdc870e6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2dc1aff8 CR3: 000000004b57d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:388 [inline]
 ktime_get_update_offsets_now+0x95/0x3e0 kernel/time/timekeeping.c:2320
 hrtimer_update_base kernel/time/hrtimer.c:659 [inline]
 hrtimer_interrupt+0x130/0x9c0 kernel/time/hrtimer.c:1855
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1107 [inline]
 __sysvec_apic_timer_interrupt+0x153/0x5a0 arch/x86/kernel/apic/apic.c:1124
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202
Code: f5 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 8f 41 f7 48 89 df e8 e6 54 42 f7 e8 31 48 65 f7 fb bf 01 00 00 00 <e8> 76 cd 35 f7 65 8b 05 f7 84 e0 75 85 c0 74 02 5b c3 e8 44 96 de
RSP: 0018:ffffc9000382fb98 EFLAGS: 00000282
RAX: 88734aabcfa98900 RBX: ffff888026e48000 RCX: 88734aabcfa98900
RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001
RBP: ffff888026e48498 R08: dffffc0000000000 R09: ffffed1004dc9001
R10: ffffed1004dc9001 R11: 1ffff11004dc9000 R12: 1ffff11004dc9093
R13: 0000000000000021 R14: dffffc0000000000 R15: 0000000000000000
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x1163/0x1350 kernel/signal.c:2874
 arch_do_signal_or_restart+0xb7/0x1240 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fcdc778efc7
Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 <0f> 05 48 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89
RSP: 002b:00007fcdc870e0e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007fcdc79e5fa8 RCX: 00007fcdc778efc9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fcdc79e5fa8
RBP: 00007fcdc79e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcdc79e6038 R14: 00007ffe82924b60 R15: 00007ffe82924c48
 </TASK>